_____________________________________________________________________
De acordo com os resultados obtidos nos procedimentos experimentais utilizados podemos concluir que:
o ângulo de flexão do joelho no contato inicial foi significativamente menor nos sujeitos com SDFP, sugerindo um padrão compensatório durante o caminhar em superfície plana e inclinada podendo ser um possível fator para caracterizar os sujeitos com essa patologia;
a atividade elétrica dos músculos VMO, VLO e VLL nos sujeitos com SDFP foi significativamente maior durante o caminhar em superfície inclinada quando comparada com a superfície plana, enquanto que nos sujeitos do grupo controle a diferença encontrada entre as duas condições não foi significativa; deste modo, concluímos que 5 graus de inclinação é suficiente para aumentar o recrutamento muscular em sujeitos com síndrome de dor femoropatelar
a atividade elétrica do músculo VLL nos sujeitos do grupo SDFP foi significativamente maior do que a atividade nos sujeitos do grupo controle durante o caminhar em superfície inclinada. A atividade elétrica dos músculos VMO e VLO foi similar entre os dois grupos nas duas condições (caminhar em superfície plana e inclinada);
a ativação do músculo VLL foi significativamente anterior a ativação do músculo VMO nos sujeitos com síndrome de dor femoropatelar, enquanto o contrário ocorreu no sujeitos do GC, independente da condição; já a ativação dos músculos VMO e VLO ocorreu de forma simultânea nos dois grupos, tanto no caminhar em superfície plana como inclinada;
devido a maior magnitude da atividade elétrica dos músculos VMO e VLL do que a do VLO e timing de ativação sincrônico dos músculos VMO e VLO nos dois grupos e nas duas condições, concluímos que durante o caminhar os músculos VMO e VLL são os responsáveis pelo controle e estabilidade patelar
refutando nossa hipótese sobre a participação do músculo VLO como estabilizador primário da patela durante o caminhar;
a diminuição no ângulo de flexão do joelho, maior atividade EMG e recrutamento anterior do VLL em comparação com o VMO são compensações apresentadas pelos sujeitos com síndrome de dor femotopatelar durante o caminhar;
o caminhar em superfície inclinada evidenciou nos sujeitos com SDFP desequilíbrio na atividade EMG em relação à magnitude do VLL e ao timing VMO-VLL, que são as mesmas alterações no sistema de controle neuromotor da articulação femoropatelar encontradas em outras atividades funcionais. Estas alterações poderiam modificar o deslizamento patelar e conseqüentemente ser um fator potencial para a manutenção e/ou agravamento da síndrome. Dessa forma, concluímos que a utilização do caminhar em esteira com inclinação de 5 graus também poderia ser utilizada como atividade funcional para avaliar os sujeitos com síndrome de dor femoropatelar, mas não para o tratamento desses pacientes.
REFERÊNCIAS BIBLIOGRÁFICAS
ADLER, N.; PERRY, J. & KENT, B. Electromyography of the vastus medialis oblique and vasti in normal subjects during gait. Electromyogr Clin Neurophysiol, 23: 643- 649, 1983.
ADAMS, W.B. Treatment option in overuse inuries of the knee: patellofemoral syndrome, iliotibial band syndrome and degenerative meniscal tears. Current Sport Medicine Reports, 3: 256-260, 2004.
AGLIETTI, P; INSALL, J.N. & CERULLI, G. Patellar pain and incongruence. I: Measurement of incongruence. Clin Orthop,176:217-24, 1983.
ALTON, F; BALDEY, L.; CAPLAN, S. & MORRISEY, M.C. A kinematic comparison of overground and treadmill walking. Clinical Biomechanics, 13: 434-440, 1998. ANDRADE, P.H.; SOAD, E.C.; OLIVEIRA, T.C., ESTURION, H.C.; BEVILAQUA-
GROSSO, D.; GIL, I.A.; BERZIN, F. & MONTEIRO-PEDRO, V. Effect of isometric exercise of knee extension at 90º associated with a rotation of the tibia in the electric activity of the muscles vastus lateralis oblique in subjects with the patellofemoral dysfunction. 12th Conference of the European Society of Biomechanics, Dublin, p 348, 2000.
ANDRADE, P.H.; BEVILAQUA-GROSSO, D.; BÉRZIN, F.; GIL, I.ª; MONTEIRO- PEDRO, V. Comparação da atividade elétrica do músculo Vasto Medial Oblíquo e Vasto Lateral Oblíquo em indivíduos com disfunção Femoropatelar. Revista de Fisioterapia da Universidade de São Paulo, v.8, n.2, p.65-71, 2001.
AREBLAD, M.; NIGG, P.M.; EKSTRAND, J.; OLSSON, K.O.. & EKSTROM, H. 3 dimensional measurement in rearfoot running. Journal of Biomechanics, 23(9): 933-940, 1990.
ARSENAULT, A.B. Treadmill versus walkway locomotion in humans: an EMG study. Ergonomics. 29: 665-676, 1986.
ARSENAUL, A.B.; WINTER, D.A.; MARTENIUK, R.G. & HAYES, K.C. How many strides are required for the analysis of electromyographic data in gait? Scand. J. Rehabil. Med., 18: 133-135, 1986.
BENOIT, D.L.; LAMONTAGNE, M.; CERULLI, G. & LITI, A. The clinical significance of electromyography normalization techniques in subjects with anterior cruciate ligament injury during treadmill walking. Gait and Posture, 18(2): 56-63, 2003. BEVILAQUA-GROSSI, D, MONTEIRO-PEDRO, V.; SOUSA, GC; SILVA, Z & BERZIN,
F. Contribution to the anatomical study of the oblique portion of the Vastus Laterallis Muscle. Braz. J. Morphol Sci. 21:47-52, 2004.
BEVILAQUA-GROSSI, D, MONTEIRO-PEDRO, V. & BERZIN, F. Análise funcional dos estabilizadores patelares. Acta Ortop Bras. 12(2): 99-104, 2004.
BOUCHER, JP, KING, MA, LEFEBVRE, R & PEPIN, A. Quadriceps femoris muscle activity in patellofemoral pain syndrome. Am J Sports Med. 20:527–532, 1992. BRANDEL, BR. Functional roles of the calf and vastus muscles in locomotion. Amer. J.
Phys. Med., 56(2):59-74, 1977
BRECHTER, J.H. & POWERS, C.M. Patellofemoral stress during walking in persons with and without patellofemoral pain. Medicine and Science and Sports and Exercise, 34(10); 1582-1593, 2002.
BROWN, D.E.; ALEXANDER, A.H. & LICHTMAN, D.M. The Elmslie-Trilat procedure evaluation in patellar dislocation and subluxation. Am. J. Sports Med., 12: 104-108, 1984.
BUCHBINDER, R.; NAPORO, N. & BIGGS, E. The relationship of abnormal pronation to chondromalacia patellae in distance runners. J. Am. Podiatry Assoc, 69(2): 159,161, 1979.
BURDEN A.M.; TREW M.; BALTZOPOULOS V. Normalisation of gait EMGs: a re- examination. J. of Electromyography and Kinesiolog. 13(6):519-32, 2003.
CALLAGHAN, M.J. & BALTZPOULOS, V. Gait analysis in patients with anterior knee pain. Clinical Biomechanics, 9:79-84, 1994.
CALLAGHAN, M.J.; OLDHAM, J.A. The role of quadriceps exercise in the treatment of patellofemoral pain syndrome. Sports Med., v.21, n.5, p.384-391, 1996.
CAYLOR D, FITES R, WORRELL TW. The relationship between quadriceps angle and anterior knee pain syndrome. JOSPT, 17(1):11-6, 1993.
CERNY, K. Vastus medialis oblique/vastus lateralis muscle activity ratios for selected exercises in persons with and without patellofemoral pain syndrome. Phys Ther. 75:672–683, 1995.
CHESWORTH, B.M.; CUULHAM, E.G.; TATA, G.E. & PEAT, M. Validation of outcome measures in patients with patellofemoral syndrome. JOSPT, 5: 302-308, 1989. CHILDS, J.D.; SPARTO, P.J.; FITZGERALD, G.K.; BIZZINI, M. & IRRGANG, J.J.
Alterations in lower extremity movement and muscle activation patterns in individuals with knee osteoarthritis. Clinical Biomechanics; 19:44-49, 2004.
CICCOTTI, MG.; KERLAN, RK.; PERRY, J. & PINK, M. An electromyographic analysis of the knee during functional activities. The normal profile. Am. J. Sports Med., 22(5):645-650, 1994.
COOK T.M.; FARRELL F.P.; CAREY I.A.; GIBBS J.M. & WIGER G.E. Effects of restricted knee flexion and walking speed on the vertical ground reaction force during gait. J Ortho Sports Phys Ther ;25:236-244, 1997.
COQUEIRO, K.R.R.; BEVILAQUA-GROSSI, D.; BERZIN, F.; SOARES, A.B.; CANDOLO, C. & MONTEIRO-PEDRO, V. Analysis on the activation of the VMO and VLL muscles during semisquat exercise with and whitout hip adduction in individuals with patellofemoral pain syndrome. J. of Electromyography and Kinesiolog. 15: 596-603, 2005.
COWAN, S.M.; BENNELL, K.L & HODGES, P.W. Therapeutic patellar taping changes the timing of vasti muscle activation in people with patellofemoral pain syndrome. Clinical Journal of Sports Medicine. 12: 339-347, 2002.
COWAN, S.M.; HODGES, P.W.; BENNELL, K.L. & CROSSLEY, K.M. Altered vastii recruitment when people with patellofemoral pain syndrome complete a postural task. Arch Phys Med Rehabil. 83: 989-995, 2002.
COWAN, S.M.; HODGES, P.W.; BENNELL, K.L. , CROSSLEY, K.M. & MCCONNELL, J. Delayed onset of electromyographic activity of vastus medialis obliquus relative to vastus lateralis in subjects with patellofemoral pain syndrome. Arch Phys Med Rehabil. 82:183-189, 2001
CROSSLEY, K. M.; COWAN, S.M.; BENNELL, K.L.; MCCONNELL, J. Knee .flexion during stair ambulation is altered in individuals with patellofemoral pain. Journal of Orthopedic Research, 22: 267-274, 2004.
CSINTALAN, RR; SCHULZ, MM; WOO, J; MCMAHON, PJ & LEE, TQ. Gender differences in patellofemoral joint biomechanics. Clinical Orthopaedics and Related Research, 402:260-269, 2002.
DAVIDSON, K. Patellofemoral pain syndrome. Am. Fam. Physician. 48: 1254-1262, 1993.
DEVERAUX M.D. & LACHMANN, S.M. Patello-femoral arthralgia in athetes attending a sports injury clinic. Br J Sports Med 18:18-21, 1984.
DILLON, P.; UPDYKE, W. & ALLEN, W. Gait analysis with reference to chondromalacia patellae. JOSPT, 5:127-131, 1983.
DOUCETTE, S.A. & GOBLE, E.M. The effect of exercise on patellar tracking in lateral patellar compression syndrome. The American J. of Spots Medicine, 20(4): 434- 440, 1992.
DYE, S.F. Invited commentary. JOSPT. 29(7): 386-387, 1999.
DYE, S.F. & VAUPEL, G.L. The pathophysiology of patellofemoral pain. Sports Med Arthroscop Rev. 2: 203-210, 1994.
EARL, JE; SCHMITZ, RJ & ARNOLD, BL. Activation of the VMO and VL during dynamic mini-squat exercise with and without isometric hip adduction. J. Electomyography Kinesiology. 11: 381-386, 2001.
FOX, T.A. Dysplasia of the quadriceps mechanism: hypoplasia of the vastus medialis muscle as related to the hypermobile patella syndrome. Surg. Clin North Am. 55: 199-206, 1975.
FRANKEL, V.H. & NORDIN, M. Basic biomechanics of the skeletal system. Philadelphia, Lea & Febiger,1980.
FULKERSON, J.P. Patologia da articulação patelofemoral, 2ed. Revinter, Rio de Janeiro, 2000.
FULKERSON, J.P. & ARENDT, M.D. Anterior knee pain in females. Clinical Orthopaedics and Related Research. 372:69-73, 2000.
GABEL, R.H. & BRAND, R. The effect of signal conditioning on the statistical analysis of gait EMG. Electroenceph. Clin. Neurophysiology. 93: 188-201, 1994.
GARRICK, JG. Anterior knee pain (chondromalacia patella). Physician Sportsmed. 17:75–84, 1989.
GILLEARD, W.; McCONNELL, J. & PARSONS, D. The effect of patellar taping on the onset of vastus medialis obliquus and vastus lateralis muscle activity in persons with patellofemoral pain. Physical Therapy, 78(1): 25-32, 1998.
GOODFELLOW, J.; HUNGERFORD, D.S. & ZINDEL, M. Patellofemoral joint mechanics and pathology, I. Funciontal anatomy of the patellofemoral joint. J Bone Joint Surg. 58B: 287-290, 1979.
GRABINER, M.D. et al.. Fatigue rates of Vastus Medialis Oblique and Vastus Lateralis during Static and Dynamic Knee Extension. J. of Orthopedic Research, v.9, p.391- 397, 1991.
GRABINER, M.D.; KOH, T.J. & ARNISH, J.T. Decreased excitation of vastus medialis oblique and vastus lateralis muscle activity persons with patellofemoral pain. Eur. J. Exp. Musculoskel. Res., 1: 33-39, 1992.
GRABINER, M.D.; KOH, T.J. & DRAGANICH, L.F. Neuromechanics of the patellofemoral pain. Medicine and Science in Sports Exercise. 26(1): 10-21, 1994.
GRAMANI-SAY, K.; PULZATTO, F.; SANTOS, G.M.; VASSIMON-BARROSO, V.; SIRIANI DE OLIVEIRA, A.; BEVILAQUA-GROSSI, D. & MONTEIRO-PEDRO, V. Efeito da rotação do quadril na síndrome da dor femoropatelar. Revista Brasileira de Fisioterapia. 10(1): 73-79, 2006.
GRANA, W.A. & KRIEGSHAUSER, L.A. The scientific basis of extensor mechanism disorders. Clin. Sports Med.. 4: 247-257, 1985.
HALLISEY, M.J.; DOHERTY, N.; BENNETT, W.F.; FULKERSON, J.P. Anatomy of the junction of the vastus lateralis tendon and the patella. J. Bone Joint Surg. 69A (4): 545-549, 1987.
HANTEN, WP & SCHULTHIES, SS. Exercise effect on electromyographic activity of the vastus medialis oblique and vastus lateralis muscles. Physical Therapy. 70:561- 565, 1990.
HARRISON, E. & MAGEE, D. Patellofemoral Pain Syndrome: The Ongoing Challenges in Etiology, Diagnosis, and Management. Critical ReviewsTM in Physical and Rehabilitation Medicine. 13(2): 253-268, 2001.
HINMAN, R.S.; BENNELL, K.L.; METCALF, B.R. & CROSSLEY, K.M. Temporal activity of vastus medialis obliquus and vastus lateralis in symptomatic knee osteoarthritis. Am J Phys Med Rehabil. 81(9):684-690, 2002a.
HINMAN, R.S.; BENNELL, K.L.; METCALF, B.R.; CROSSLEY, K.M. Delayed onset of quadriceps activity and altered knee joint kinematics during stair stepping in individuals with knee osteoarthritis. Arch. Phys. Med. Rehabil. 83: 1080-1086, 2002b.
HUNG, Y.; GROSS, M.T. Effect of foot position on electromyographic activity of Vastus Medialis Oblique and Vastus Lateralis during Lower extremity weight-bearing activities. J. Orthopaedic & Sports Physical Ther., v.29, n.2, p.93-105, 1999. HUNGERFORD, DS & BARRY, M. Biomechanics of the patellofemoral joint. Clin.
Orthop. 144: 9-15, 1979.
HURWITZ, D.E.; RYALS, A.R.; BLOCK, J.A.; SHARMA, L.; SCHNITZER, T.J. & ANDRIACCHI, T.P. Knee pain and joint loading in subjects with osteoarthritis of the knee. Journal Orthop. Research, 18:572-579, 2000.
INGERSOLL, CD & KNIGHT, KL. Patellar location changes following EMG biofeedback or progressive resistive exercises. Med Sci Sports Exerc. 23:1122–1127, 1991. INSALL, J. Patellar malalignment syndrome. Orthop. Clin. North Am. 10: 117-122,
1979.
---. Current concepts review: patellar pain. J. Bone Joint Surgery. 64A: 147-152, 1982.
JACOBSON, WC; GABEL, RH & BRAND, RA. Surface vs. fine-wire electrode ensemble-averaged signals during gait. J. Electromyography Kinesiology, 5(1):37-44, 1995.
JOHNSTON, L.B. & GROSS, M.T. Efeects of foot orthoses on quality of life for individuals with patellofemoral pain syndrome. JOSPT, 34: 440-448, 2004.
KADABA, M.P.; RAMAKRISHNAN, H.K.; WOOTEN, M.E.; GAINEY, J.; GORTON, G. & COCHRAN, G.V.B. Repeatability of kinematic, kinetic, and electromyographic data in normal adult gait. Journal of Orthopedic Research. 7(6):849-860, 1989.
KARIN, A.J.; COLEMAN, A.; WISNOM, M.R. & ADAMS, M.A. Propagation of surface fissures in articular cartilage in response to cyclic loading in vitro. Clinical Biomechanics, 18:960-968, 2003.
KARST, G.M. & WILLET, G.M. Onset timing of electromyographic activity in the vastus medialis oblique and vastus lateralis muscles in subjects with and without patellofemoral pain. Physical Therapy, 75: 813-823, 1995.
KAUFMAN, K.R.; HUGHES, C.; MORREY, B.F.; MORREY, M. & AN, K.N. Gait characteristics of patients with knee osteoarthritis. Journal of Biomechanics, 34:907-915, 2001.
KIRTLEY C., WHITTLE M.W., JEFFERSON R.J. Influence of walking speed on gait parameters. J Biomed Eng. 7(4):282-8, 1985.
KNUTSON, L.M.; SODERBERG, G.L.; BALLANTYNE, B.T. A study of various normalization procedures for within day electromyographic data. J. Electromyogr. Kinesiol. 4 (1): 47-59, 1994.
LANGE, GW, HINTERMEISTER, RA, SCHLEGEL, T, DILLMAN, CJ & STEADMAN, JR. Electromyographic and kinematic analysis of graded treadmill walking and the implications for knee rehabilitation. JOSPT. 23(5):294-301, 1996.
LAPRADE J., CULHAM E., BROUWER B., Comparison of five isometric exercises in the recruitment of the vastus medialis oblique in persons with and without patellofemoral pain syndrome. JOSPT. 27(3):197-204, 1998.
LIEB, FJ & PERRY, J. Quadriceps function: an anatomic and mechanical study using amputaded limbs. J. Bone Joint Surg Am. 50:1535-1548, 1968.
LIVINGSTON, L.A. & MANDIGO, J.L. Bilateral Q angle assimetry and anterior knee pain syndrome. Clinical Biomechanics, 14: 7-13, 1999.
LOHMAN III, E.B. A critical review of patellofemoral pain syndrome in rehabilitation. Critical Review in Physical and Rehabilitation Medicine, 14(34): 197-222, 2002. LOUDON, J.K.; WIESNERT, D., GOIST-FOLEY, H.L.; ASJEST, C. & LOUDON, K.
Intrarater reliability of functional performance tests for subjects with patellofemoral pain syndrome. Journal of Athletic Training. 37(3):256-261, 2002
MADELINE, P; VOIGHT, M. & ARENDT-NALESEN, L. Reorganisation of human step initiation during experimental muscle pain. Gait & Posture, 10: 240-247, 1999. MAGEE, D.J. Avaliação Musculoesquelética. 3ed, Editora Manole, 2002
MANSKE, R.C. & DAVIES, G.J. A nonsurgical approach to examination and treatment of the patellofemoral join, part 1: examination of the patellofemoral joint. Critical Review in Physical and Rehabilitation Medicine. 15(2): 141-166, 2001.
MANSKE, R.C.; SMITH, B.S. & WYATT, F. Test-retest reliability of lower extremity functional tests after a closed kinetic chain isokinetic bout. J. Sport Rehabilitation. 12:119-132, 2003.
MATSAS, A.; TAYLOR, N & MCBURNEY, H. Knee joint kinematics from familiarized treadmill walking can be generalized to overground walking in young unimpaired subjects. Gait and Posture, 11: 46-53, 2000.
McCONNELL J.S.: The management of chondromalacia patellae: A long term solution. Australian J Physiotherapy, 32 (4): 215-223, 1986.
--- Management of patellofemoral problems. Man Manip Ther. 1:60-66, 1996.
McINTYRE, D.I. & ROBERTSON, G.E: Quadriceps muscle activity in women runners with and without patellofemoral pain syndrome. Arch Phys Med rehabil. 73: 10-14, 1992
MERCHANT, A.C. Classification of patellofemoral disorders Arthroscopy. 4: 235240, 1988.
MESSIER, S.P.; LOESER, R.F; HOOVER, J.L.; SEMBLE, E.L. & WISE, C.M. Osteoarthritis of the knee: effects on gait, strength and flexibility. Arch. Phys. Med. Rehabilitation, 73:29-36, 1992.
MICHAEL, F. & POWERS, C.M. Practical management of patellofemoral pain. Clinical Journal of Sport Medicine. 12(1): 36-38, 2002.
MILGROM, C.; KEREM, E. & FINESTONE, A. Patellofemoral pain caused by overactivity: a prospective study of risk factors in infantry recruits. Journal Bone Joint Surgery American, 73: 1041-1043, 1991.
MOLLER, B.; KREBS, B; TIDEMAND-DAL, C. & AARIS, K. Isometric contractions in the patellofemoral pain syndrome. Arch Orthop Trauma Surg. 105: 24-27, 1986. MOHR, K.J.; KVITNE, R.S.; PINK, M.M.; FIDELER, B. & PERRY, J. Electromyography
of the quadriceps in patellofemoral pain with patellar subluxation. Clinical Orthopaedics and Related Research. 415: 261-271, 2003.
MONTEIRO-PEDRO, V. Electromyographic activity of Vastus Medialis Oblique muscle in the step-up and step-down exercises. Brazilian J. Morphological Science, v.14, n.1, p.19-23, 1997.
MORRISH, G.M. & WOLEDGE, R.C. A comparison of the activation of muscles moving the patella in normal subjects and in patients with chronic patellofemoral problems. Scand J Rehab Med. 29:43-48, 1997.
MORRISH, GM, WOLEDGE, RC & HADDAD, FS. Activity in three parts of the quadriceps recorded isometrically at two different knee angles and during a functional exercise. Electromyogr Clin Neurophysiol. 43(5):259-65, 2003.
MOSS, M.P. Nuances determine management of patellofemoral pain – subtle anatomical differences affect biomechanics and must be accounted for when prescriginb treatment. Biomechanics. 1: 43-45, 2003.
MÜNDERMANN, A.; DYRBY, C.O. & ANDRIACCHI, T.P. Secondary gait changes in patients with medial compartment knee osteoarthritis. Arthritis & Rheumatism. 52(9): 2835-2844, 2005.
MURRAY, M.P.; SPURR, G.B.; SEPIC, S.B.; GARDNER, G.M. & MOLLINGER, L.A. Treadmill vs. floor walking: kinematics, electromiogram, and heart rate. Journal of Applied Physiology. 59(1):87-91, 1985.
NADEAU, S.; GRAVEL, D.; HÉBERT, L.J.; ARSENAULT, A.B. & LEPAGE, Y. Gait study of patients with patellofemoral pain syndrome. Gait & Posture, 5:21-27, 1997. NEPTUNE, R.R.; WRIGHT, I.C. & VAN DEN BOGERT, A.J. The influence of orthotic
devices and vastus medialis strength and timing on patellofemoral loads during running. Clinical Biomechanics, 15: 611-618, 2000.
NISSEN, C.W.; CULLEN, M.C.; HEWETT, T.E. & NOYES, F.R. Physical and arthroscopic examination techniques of the patellofemoral joints. JOSPT. 28(5): 277-285, 1998.
NUNES, C. Efeito do exercício isométrico de extensão do joelho associado à adução do quadril e a rotação da tíbia no Leg-press na atividade elétrica dos músculos Vasto Medial Oblíquo, Vasto Lateral Longo e Vasto Lateral Oblíquo. São Carlos, 2002. 193p. Dissertação de Mestrado – Programa de Pós-graduação em Fisioterapia, Universidade Federal de São Carlos.
OWINGS, T.M. & GRABINER, M.D. Motor control of the vastus medialis oblique and vastus lateralis muscles is disrupted during eccentric contractions in subjects with patellofemoral pain. Am J. Sports Med. 30: 483-487, 2002.
PAPAGELOPOULOS, P.J. & SIM, F.H. Patellofemoral pain syndrome: diagnosis and management. Orthopedics. 20: 148-157, 1997.
PERRY, J. Gait analysis: normal and pathological function. Thorofare, Slack Inc, 1992.
POWERS, CM. Rehabilitation of patellofemoral joint disorders: a critical review. JOSPT. 345-34, 1998.
---. Patellar Kinematics, part 1: the influence of vastus muscle activity in subjects with and without patellofemoral pain. Physical Therapy. 80(10):956-964, 2000.
--- The influence of altered lower-extremity kinematics on patellofemoral joint dysfunction: a theoretical perspective. JOSPT, 33(11): 639-646, 2003.
POWERS, C.M.; HEINO, J.G.; RAO, S. & PERRY, J. The influence of patellofemoral pain on lower limb loading during gait. Clinical Biomechanics, 14: 722-728, 1999. POWERS, C.M.; LANDEL, R. & PERRY, J. Timing and intensity of vastus muscle
activity during functional activities in subjects with and without patellofemoral pain. Physical Therapy, 76(9):945-955, 1996.
POWERS, C.M.; PERRY, J.; HSU, A. & HISLOP H.J. Are patellofemoral pain and quadriceps femoris muscle torque associated with locomotor function. Physical Therapy, 77(10):1063-1078, 1997.
POWERS, C.M.; PERRY, J & SHELLOCK, F.G. The relationship between vasti EMG patterns and patellar tracking during active knee extension (abstract). Med Sci Sports Exerc. 29: 281, 1997.
POWERS, C.M.; WARD, S.R.; FREDERICSON, M.; GUILLET, M & SHELLOCK, F.G. Patellofemoral kinematics during weight-bearing and non—weight-bearing knee extension in persons with lateral subluxation of the patella: a preliminary study. JOSPT, 33(11):677-685, 2003.
PULZATTO, F. Atividade elétrica dos músculos estabilizadores da patela em indivíduos portadores da síndrome da dor femoropatelar durante exercícios realizado no step.São Carlos, 2005. Dissertação de Mestrado – Programa de Pós- graduação em Fisioterapia, Universidade Federal de São Carlos.
PULZATTO, F.; GRAMANI-SAY, K; .SIQUEIRA, A.C.B. de; SANTOS, G.M.; BEVILAQUA-GROSSI, D.; OLIVEIRA, ªS. de; MONTEIRO-PEDRO, V. A influência da altura do step no exercício de subida posterior: estudo eletromiográfico em indivíduos sadios e portadores da síndrome da dor femoropatelar. Acta Ortopédica Brasileira. 13(4): 168-170, 2005.
RADIN, E.L.; YANG, K.H.; RIEGGER, C.; KISH, V.L. & O’CONNOR, J.J. Relationship between lower limb dynamics and knee joint pain. Journal of Orthop. Research, 9:398-405, 1991.
REYNOLDS, L; LEVIN, T.; MEDEIROS, J.; ALDER, N. & HALLUM, A EMG activity of VMO and VL and their role in patellar alignment. Am J Phys Med. 2: 61-71, 1983. RUFIN, M.T. & KININGHAM, R.B. Anterior knee pain: the challenge of patellofemoral
SAKAI, N.; LUO, Z.P.; RAND,J.A. & AN, K.N. The influence of weakness in the vastus medialis oblique muscle on the patellofemoral joint: an in vitro biomechanical study. Clinical Biomechanics. 15: 335-339, 2000.
SANCHIS-ALFONSO, V.; ROSELLO-SASTRE, E. Immunohistochemical analysis for neural markers of the lateral retinaculum in patients with isolated symptomatic patellofemoral malalignement. Am. J. Sports Med. 28: 725-731, 2000.
SANCHIS-ALFONSO, V.; ROSELLO-SASTRE, E.; MONTEAGUDO-CASTRO, C. & ESQUERDO, J. Quantitative analysis of nerve change in the lateral retinaculum in patients with isolated symptomatic malalignment : a preliminary study. Am J Sports Med. 26(5): 703-709, 1998.
SANFRIDSSON, J.; ARNBJÖRNSSON, A.; FRIDE, T.;RYD, L.;SVAH, G. & JONSSON, K. Femorotibial rotation and the Q angle related the dislocatting patella. Acta Radiológica, 42: 218–224, 2001.
SCHULTHIES, S.S.; FRANCIS, R.S.; FISCHER, A.G. & GRAAFF, V.D. Does the Q angle reflexts the force on the patella in the frontal plane? Physical Therapy, 75(1): 30-36, 1995.
SENIAM Surface EMG non-invasive assessment of muscle. European Recommendations for Surface Electromyography. Index 8- Roessing Research and Development, ISBN 90-75452-15-2, p.115, 1999.
SERRÃO, F.V.; CABRAL, C.M.N.; BÉRZIN, F.; CANDOLO, C.; MONTEIRO-PEDRO, V. Effect of tibia rotation on the electromyographical activity of the vastus medialis oblique and vastus lateralis longus muscles during isometric leg press. Physical Therapy in Sports, 6(1): 15-23, 2005
SHEEHY, P.; BURDETT, R.G.; IRRGANG, J.J. & VANSWEARINGEN, J. An electromyographic study of vastus medialis oblique and vastus lateralis activity while ascending and descending steps. J. Orthop Sports Phys Ther 27(6): 423-429, 1998.
SHELTON G.L.; THIGPEN, L.K. Rehabilitation of patellofemoral dysfunction: A Review of literature. J. Orthopaedic and Sports Physical Ther., v.14, n.6, p.243-249, 1991.
SMIDT, GL. Biomechanical analysis of knee flexion and extension. J. Biomechanics. 6:79-92, 1973
SMITH, G.; HOWE, T.; OLDHAM, J.; PETTERSON, T.; TALLIS, R. & VICKERS, G. Assessing quadriceps muscle recruitment order using rectified average surface EMG in young normals and weak and healthy elderly subjects. Clin Rehabil. 9: 40- 46, 1995.
SOUZA, D.R., & GROSS, M.T. Comparison of vastus medialis obliquus: Vastus lateralis muscle integrated electromyographic ratios between healthy subjects and patients with patellofemoral pain. Phys Ther., 71: 310–320, 1991.
SPENCER J.D., HAYES, K.C. & ALEXANDER, I.J. Knee joint effusion and quadriceps reflex innibition in man. Arch. Phys. Med. Rehabili., 65:171-177, 1984.
STEINKAMP, L.A.; DILLINGHAM, M.F.; MARKEL, M.D.; HILL, J.A. & KAUFMAN, K.R. Biomechanical consideration in patellofemoral joint rehabilitation. Am. J. Sports Medicine, 21: 438-444, 1993.
STOLTZE, H..; KUHTZ-BUSCHBECK, J.P.; MONDWURF, C.; BOCZEK-FUNCKE, A.; JÖHNK, K.; DEUSCHL, G. & ILLERT, M. Gait analysis during treadmill and overground locomotion in children and adults. Electroenc. And Clin. Neurophysiology. 105: 490-497, 1997.
STRATHY, G.M.; CHAO, L.Y. & LAUGHMAN, R.K. Changes in knee function